(internal_set_property): don't abort on

[lilypond.git] / lily / grob-property.cc

diff --git a/lily/grob-property.cc b/lily/grob-property.cc
index 8c68171fa92eaae76f688c8286c475f0384eb4f4..c4dce927b43f86f3265348779ede3ef846f6b1b9 100644 (file)
--- a/lily/grob-property.cc
+++ b/lily/grob-property.cc
@@ -55,6 +55,7 @@ Grob::internal_set_property (SCM sym, SCM v)
     {
       if (!ly_is_procedure (v)
          && !is_simple_closure (v)
+         && v != ly_symbol2scm ("calculation-in-progress") 
          && !type_check_assignment (sym, v, ly_symbol2scm ("backend-type?")))
        abort ();
       check_interfaces_for_property (this, sym);